<?php

if (!defined('BASEPATH'))
    exit('No direct script access allowed');
/**
 * Code Igniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		Rick Ellis
 * @copyright	Copyright (c) 2006, pMachine, Inc.
 * @license		http://www.codeignitor.com/user_guide/license.html
 * @link		http://www.codeigniter.com
 * @since		Version 1.0
 * @filesource
 */
// ------------------------------------------------------------------------

/**
 * PayPal_Lib Controller Class (Paypal IPN Class)
 *
 * This CI library is based on the Paypal PHP class by Micah Carrick
 * See www.micahcarrick.com for the most recent version of this class
 * along with any applicable sample files and other documentaion.
 *
 * This file provides a neat and simple method to interface with paypal and
 * The paypal Instant Payment Notification (IPN) interface.  This file is
 * NOT intended to make the paypal integration "plug 'n' play". It still
 * requires the developer (that should be you) to understand the paypal
 * process and know the variables you want/need to pass to paypal to
 * achieve what you want.  
 *
 * This class handles the submission of an order to paypal as well as the
 * processing an Instant Payment Notification.
 * This class enables you to mark points and calculate the time difference
 * between them.  Memory consumption can also be displayed.
 *
 * The class requires the use of the PayPal_Lib config file.
 *
 * @package     CodeIgniter
 * @subpackage  Libraries
 * @category    Commerce
 * @author      Ran Aroussi <ran@aroussi.com>
 * @copyright   Copyright (c) 2006, http://aroussi.com/ci/
 *
 */
// ------------------------------------------------------------------------

class Paypal_Lib {

    var $last_error;   // holds the last error encountered
    var $ipn_log;    // bool: log IPN results to text file?
    var $ipn_log_file;   // filename of the IPN log
    var $ipn_response;   // holds the IPN response from paypal	
    var $ipn_data = array(); // array contains the POST values for IPN
    var $fields = array();  // array holds the fields to submit to paypal
    var $submit_btn = '';  // Image/Form button
    var $button_path = '';  // The path of the buttons
    var $CI;

    function Paypal_Lib() {
        $this->CI = & get_instance();
        $this->CI->load->helper('url');
        $this->CI->load->helper('form');
        $this->CI->load->config('paypallib_config');

        //$this->paypal_url = 'https://www.paypal.com/cgi-bin/webscr';
        $this->paypal_url = 'https://www.sandbox.paypal.com/cgi-bin/webscr';

        $this->last_error = '';
        $this->ipn_response = '';

        $this->ipn_log_file = $this->CI->config->item('paypal_lib_ipn_log_file');
        $this->ipn_log = $this->CI->config->item('paypal_lib_ipn_log');

        $this->button_path = $this->CI->config->item('paypal_lib_button_path');

        // populate $fields array with a few default values.  See the paypal
        // documentation for a list of fields and their data types. These defaul
        // values can be overwritten by the calling script.
        $this->add_field('rm', '2');     // Return method = POST
        $this->add_field('cmd', '_xclick');

        $this->add_field('currency_code', $this->CI->config->item('paypal_lib_currency_code'));
        $this->add_field('quantity', '1');
        $this->button('Pay Now!');
    }

    function button($value) {
        // changes the default caption of the submit button
        $this->submit_btn = form_submit('pp_submit', $value);
    }

    function image($file) {
        $this->submit_btn = '<input type="image" name="add" src="' . site_url($this->button_path . '/' . $file) . '" border="0" />';
    }

    function add_field($field, $value) {
        // adds a key=>value pair to the fields array, which is what will be 
        // sent to paypal as POST variables.  If the value is already in the 
        // array, it will be overwritten.
        $this->fields[$field] = $value;
    }

    function paypal_auto_form() {
        // this function actually generates an entire HTML page consisting of
        // a form with hidden elements which is submitted to paypal via the 
        // BODY element's onLoad attribute.  We do this so that you can validate
        // any POST vars from you custom form before submitting to paypal.  So 
        // basically, you'll have your own form which is submitted to your script
        // to validate the data, which in turn calls this function to create
        // another hidden form and submit to paypal.

        $this->button('Click here if you\'re not automatically redirected...');

        echo '<html>' . "\n";
        echo '<head><title>Processing Payment...</title></head>' . "\n";
        echo '<body onLoad="document.forms[\'paypal_auto_form\'].submit();">' . "\n";
        echo '<p>Please wait, your order is being processed and you will be redirected to the paypal website.</p>' . "\n";
        echo $this->paypal_form('paypal_auto_form');
        echo '</body></html>';
    }

    function paypal_form($form_name = 'paypal_form') {
        $str = '';
        $str .= '<form method="post" action="' . $this->paypal_url . '" name="' . $form_name . '"/>' . "\n";
        foreach ($this->fields as $name => $value)
            $str .= form_input($name, $value) . "\n";
        $str .= '<p>' . $this->submit_btn . '</p>';
        $str .= form_close() . "\n";

        return $str;
    }

    function validate_ipn() {
        // parse the paypal URL
        $url_parsed = parse_url($this->paypal_url);

        // generate the post string from the _POST vars aswell as load the
        // _POST vars into an arry so we can play with them from the calling
        // script.
        $post_string = '';
        if ($this->CI->input->post()) {
            foreach ($this->CI->input->post() as $field => $value) {
                $this->ipn_data[$field] = $value;
                $post_string .= $field . '=' . urlencode(stripslashes($value)) . '&';
            }
        }

        $post_string.="cmd=_notify-validate"; // append ipn command
        // open the connection to paypal
        $fp = fsockopen($url_parsed['host'], "80", $err_num, $err_str, 30);
        if (!$fp) {
            // could not open the connection.  If loggin is on, the error message
            // will be in the log.
            $this->last_error = "fsockopen error no. $errnum: $errstr";
            $this->log_ipn_results(false);
            return false;
        } else {
            // Post the data back to paypal
            fputs($fp, "POST $url_parsed[path] HTTP/1.1\r\n");
            fputs($fp, "Host: $url_parsed[host]\r\n");
            fputs($fp, "Content-type: application/x-www-form-urlencoded\r\n");
            fputs($fp, "Content-length: " . strlen($post_string) . "\r\n");
            fputs($fp, "Connection: close\r\n\r\n");
            fputs($fp, $post_string . "\r\n\r\n");

            // loop through the response from the server and append to variable
            while (!feof($fp))
                $this->ipn_response .= fgets($fp, 1024);

            fclose($fp); // close connection
        }

        if (eregi("VERIFIED", $this->ipn_response)) {
            // Valid IPN transaction.
            $this->log_ipn_results(true);
            return true;
        } else {
            // Invalid IPN transaction.  Check the log for details.
            $this->last_error = 'IPN Validation Failed.';
            $this->log_ipn_results(false);
            return false;
        }
    }

    function log_ipn_results($success) {
        if (!$this->ipn_log)
            return;  // is logging turned off?
        // Timestamp
        $text = '[' . date('m/d/Y g:i A') . '] - ';

        // Success or failure being logged?
        if ($success)
            $text .= "SUCCESS!\n";
        else
            $text .= 'FAIL: ' . $this->last_error . "\n";

        // Log the POST variables
        $text .= "IPN POST Vars from Paypal:\n";
        foreach ($this->ipn_data as $key => $value)
            $text .= "$key=$value, ";

        // Log the response from the paypal server
        $text .= "\nIPN Response from Paypal Server:\n " . $this->ipn_response;

        // Write to log
        $fp = fopen($this->ipn_log_file, 'a');
        fwrite($fp, $text . "\n\n");

        fclose($fp);  // close file
    }

    function dump() {
        // Used for debugging, this function will output all the field/value pairs
        // that are currently defined in the instance of the class using the
        // add_field() function.

        ksort($this->fields);
        echo '<h2>ppal->dump() Output:</h2>' . "\n";
        echo '<code style="font: 12px Monaco, \'Courier New\', Verdana, Sans-serif;  background: #f9f9f9; border: 1px solid #D0D0D0; color: #002166; display: block; margin: 14px 0; padding: 12px 10px;">' . "\n";
        foreach ($this->fields as $key => $value)
            echo '<strong>' . $key . '</strong>:	' . urldecode($value) . '<br/>';
        echo "</code>\n";
    }

}

?>